Poker rooms make money out of you as an online poker player by charging rake every real money game you play. If you play cash games, the poker room takes a percentage out of every pot when a flop is seen. If you play tournaments or Sit & Go's, the rake is the amount after the plus. So for a tournament with a buy in of $1 + $.20 you pay 20 cents to the poker room and $1 goes into the prize pool. There are several ways for you to get a piece of the rake you paid back. These are first deposit bonuses, kickback bonuses and rakeback.
To attract new players they can make money from poker rooms often offer a first deposit bonus, mostly expressed as a percentage of your first deposit up to a certain maximum. For example, a 100% $600 bonus with a first deposit of $50, results in a $50 dollar bonus. If you deposit more than $600, you won't get a larger bonus than $600. Usually you have to meet certain requirements to convert the bonus dollars into real dollars in your account ('clearing' the bonus). Most of the time this means you have to earn a certain amount of player points per dollar. Bonuses can be released in increments or in a lumpsum. If a bonus does not release in small increments and can't be partially redeemed, you have to make sure you can meet the clearing requirements before the bonus expires.
Information about first deposit bonuses for different online poker rooms can be found in the online poker room reviews.
Poker rooms also reward 'third parties' for bringing new players to them. Kickback affiliates are such a third party. Whenever you sign up through a kickback affiliate, they get a reward from the poker room and 'kick back' part of this reward to you, the poker player who they owe their income to. Such a kick back can be in the form of points, items and dollars. This type of bonus also requires you to play a certain amount (earn a certain amount of player points), but the requirements are usually relatively much lower than for a first deposit bonus.
Another way to get part of your paid rake back is by rakeback. Rakeback is calculated as a percentage of your monthly gross revenue (MGR), which is the amount you have paid in rake in one month according to the poker room's calculation method.
Some poker rooms give out rakeback to their players themselves, for other rooms you have to sign up through a rakeback affiliate in order to be eligible for rakeback. If you have to sign up through an affiliate it is important to know that you can't get rakeback if you already opened a real money account without rakeback at that poker room. So if you sign up at a poker room through a kickback affiliate for their kickback bonus, you won't be able to receive any rakeback at that particular poker room in the future ever (unless you sign up under your girlfriend's or whoever's persona).
This is exactly the reason why I would advise not to do a kickback promotion at a poker room like Full Tilt Poker. This room offers 27% rakeback if you sign up through an affiliate. It is also an independent room. This means you can't sign up for rakeback at another skin to play the same games as with poker room networks. Furthermore this room is so large and offers so many games that you will very likely keep playing there over time and therefore eventually 'make more money' in rakeback than with the quick and easy kickback bonus.
It is possible to receive both a first deposit bonus and a kickback bonus at the same time. Keep in mind however that the first deposit bonus will often clear much more slowly than the kickback bonus. Therefore it would be advisable, certainly when playing lower stakes, to deposit so little that your first deposit bonus will be fully cleared as soon as you meet the requirements for the kickback. If this first deposit does not meet the minimum deposit requirements for the kickback bonus, you can solve this by making a second deposit directly after the first one.
A first deposit bonus can also be cleared while receiving rakeback. Often the amount of bonus cleared will be deducted from your MGR resulting in a lower amount of rakeback for that period. However, the bonus and rakeback combined will always result in a higher percentage of your rake back than just the bonus or just the rakeback.
Information regarding first deposit bonuses and rakeback for specific poker rooms can be found in the poker room reviews
Two major kickback affiliates are PokerSource and PokerSavvy. I found both to be very reliable and points will be added to your account within a couple of days after clearing a bonus. If you aren't interested in the items you can purchase in the points store of both these kickback affiliates, then you can turn your points into dollars. With PokerSavvy this can be done by purchasing a moneybookers deposit, which means you'll need a moneybookers account). At PokerSource you can turn points into dollars by purchasing poker gift cards, giving you a deposit at one of a number of different poker rooms of your choice.
When signing up through a rakeback affiliate it is important to make sure your affiliate is reliable. A rakeback affiliate I have had very good experience with is RakeTheRake. RakeTheRake is the biggest rakeback affiliate out there. They provide good and quick support for their costumers. Because RakeTheRake is such a large affiliate they can afford to offer large freerolls and rake races for a lot of the poker rooms on top of their rakeback. Another big and reliable rakeback affiliate would be RakeBrain.
There are also quite a number of smaller affiliates out there that can sometimes arrange a little extra's like a certain bonus at poker rooms which the big affiliates don't promote. I would advice you to be very careful in picking such an affiliate as there are plenty of people trying to scam you for a piece of the rake you pay to a poker room.